74 
FLORIDA GEOLOGICAL SURVEY—THIRD ANNUAL REPORT. 
however, that of spouting is certainly the most striking and re¬ 
markable. 
In considering the use of wells for drainage purposes the re¬ 
lation of the lake basin to the underground water level should 
first be definitely determined. The effectiveness of the well is re¬ 
duced as the water level is approached, and it is of course obvious 
that the water in the lake can in no case be carried below the under-, 
ground water level. Many of the larger lake basins are known to 
lie very close to the water level. If the lake basin lies as low as the 
permanent water level it is obvious that the water in the lake can 
not be drained by wells, moreover since the effectivness of the well 
is affected by the near approach to the water level, it is hardly prac¬ 
ticable to reduce the water in the lake quite to the permanent under¬ 
ground water level. It must also be borne in mind that while the un¬ 
derground water is a permanent supply the water level or water line 
is not stationary, but varies with the seasons. The amount of varia¬ 
tion for the locality concerned should be determined. 
The fact that a lake basin stands soqiewhat above the water line 
at the close of a long dry season is not proof that it will be found to 
stand above the water line after a season of heavy rainfall. In 
some sections of the state the range of variation of the water line 
has been found to be as much as ten feet, and may in some instances- 
exceed that amount. 
The relation between the level of the lake basin and the under¬ 
ground water has been determined for a few of the lakes. Meas¬ 
urements of Alachua Lake were made in 1907 and again in 1909. 
When measured in October, 1907, the water level in Alachua Lake 
was found to be 2.01 feet above the level of the underground 
water of the Vicksburg Limestone formation as determined from 
the Gainesville City well.* When measured in November, 1909. 
the water in the sink stood approximately 1.4 feet above the water 
level in the limestone as indicated by the city well. At the time 
these measurements were made the lake was at a low water stage. 
The underground water level was likewise at a low stage. From 
these measurements it appears that Alachua Lake during the dry 
seasons at least is lowered by natural drainage through the sink 
to or practically to the underground water level. During the rainy 
season the water in the lake doubtless rises above this level, although 
it must be borne in mind that the water line also rises during the 
rainy season. It is evident, therefore, that the difference between 
the water level in the lake and the underground water line is great - 
*For a record of this well, see Bull. No. 1, pp. 30 and 88-89, 1908. 
